Study on the suppression effect of dynamic vibration absorbers on abnormal vibration of railway vehicle

The phenomenon of abnormal axle box vibration in high-speed railway vehicles was analyzed based on measured vertical acceleration data of the axle box at different vehicle speeds. The results show that abnormal vibration occurs when the vehicle speed exceeds 350 km/h, with the frequency mainly concentrated around 40 Hz. To investigate the cause of the abnormal vibration, a vehicle-rail coupling system dynamics model was established, and the cause was analyzed through dynamic simulations. The analysis reveals that, when the vehicle speed exceeds 350 km/h, the coupling effect between wheel eccentric excitation frequency and P2 resonance frequency leads to vertical abnormal vibration of the axle box, with the most intense vibration occurring at 400 km/h. To resolve this issue, a solution is proposed to install a Dynamic Vibration Absorber (DVA) in the vertical direction of the axle box. When the mass ratio of the DVA is between 0.15 and 0.2 and the damping ratio is between 0.12 and 0.2, this method effectively suppresses the abnormal vibration of the axle box at 400 km/h, while avoiding excessive vibration acceleration at lower or higher speeds. This approach provides an effective solution for controlling abnormal axle box vibrations in high-speed railway vehicles.